Monte–Carlo simulation of crystallization in single‐chain square‐well homopolymers

Wicks, Thomas J.; Wattis, Jonathan A. D.; Graham, Richard S.

Abstract

© 2020 Wiley Periodicals LLC We present Monte–Carlo (MC) simulations of the crystallization transition of single-chain square-well homopolymers, with a continuous description of monomer positions. For long chains with short-ranged interactions this system shows a strong configurational bottleneck, which makes it difficult to explore the whole configuration space. To surmount this problem we combine parallel tempering with a nonstandard choice of tempering levels, a bespoke biasing strategy and a method to map results between different temperatures. We verify that our simulations mix well when simulating chains of 128 and 256 beads. Our simulation approach resolves issues with reproducibility of MC simulations reported in prior work, particularly for the transition region between the expanded coil and crystalline region. We obtain highly reproducible results for both the free energy landscape and the inverse temperature, with low statistical noise. We outline a method to extract the free energy barrier, at any temperature, for any choice of order parameter, illustrating this technique by computing the free energy landscape as a function of the Steinhardt–Nelson order parameter for a range of temperatures.

Citation

Wicks, T. J., Wattis, J. A. D., & Graham, R. S. (2021). Monte–Carlo simulation of crystallization in single‐chain square‐well homopolymers. Polymer Crystallization, 4(1), Article e10146. https://doi.org/10.1002/pcr2.10146

• Journal Article Type: Article
• Acceptance Date: Jul 27, 2020
• Online Publication Date: Aug 22, 2020
• Publication Date: 2021-02
• Deposit Date: Jul 29, 2020
• Publicly Available Date: Aug 23, 2021
• Journal: Polymer Crystallization
• Print ISSN: 2573-7619
• Electronic ISSN: 2573-7619
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 4
• Issue: 1
• Article Number: e10146
• DOI: https://doi.org/10.1002/pcr2.10146
• Keywords: Monte-Carlo simulation; single chain; square-well potential
• Public URL: https://nottingham-repository.worktribe.com/output/4794955
• Publisher URL: https://onlinelibrary.wiley.com/doi/abs/10.1002/pcr2.10146